Process of impermeabilizing, tightening, or consolidating grounds and other earthy and stony masses and structures



PROCESS OF IMPERMEABILIZING, TIGHT- ENING, R. CONSOLIDATING GROUNDS ANDOTHER EARTHY AND STONY MASSES AND STRUCTURES Gerrit Hendrik van Leeuwen,Amsterdam, Netherlands, assignor to Shell Development Company, SanFrancisco, Calif., a corporation of Delaware No Drawing. Originalapplication September 18, 1936, Serial No. 101,426. Divided and thisapplication February 23, 1940, Serial No. 320,428.

Patented May 11, 1943 In the Netherlands October '7, 1935 3 Claims.

This application isa division of my co-pending application, Serial No.101,426, filed September 18, 1936,-which issued as Patent 2,197,843April 23, 1940.

The invention concerns a process for improving the cohesion of and forimpermeabilizing and consolidating grounds and other earthy masses, suchas subsoil sandor gravel layers, natural and artificial rocks, masonryor concrete structures, stone dumpings, pile works and the like, byfilling up and tightening the voids, cavities, fissuresand such likeinterruptions of the mass. The present process may be applied, forexample, for providing screens impervious or substantially im-. perviousto water and gases in porous and waterbearing soils, tightening seepingdikes, tunnels or cellar walls, consolidating loose soils, such as thosefor foundations or dike bodies, fixing masses of bog, river beds orshifting sands, tightening cracks and fissures in rock formations,sealing joints in stone-settings and concrete, filling up and unitingstone-dumpings either before, during or after construction, sealingwells or borehole walls, such as in the winning of petroleum oil.

It is already known for the said purposes to treat the ground or othermass with impregnating agents of various kinds, such as aqueous bitumendispersions, cement or clay suspensions and precipitate-formingchemicals.

.The process according to the invention consists in supplying into thevoids of the masses to be treated a substance which is capable ofswelling through a solvating agent, the particles of which substance arecoated with a substance repelling the solvating agent, the swelling ofthe said particles being effected in the mass under treatment byattracting, or absorbing, or combining with, or wetting by the saidsolvating agent;

Where the solvating agent consists of water or aqueous solution ordispersion, the swellable substance may comprise either inorganic ororganic hydrophile colloids. Among inorganic hydrophile colloids thatmay be used are the more or less colloidal kinds of clays, hydroxides ofpolyvalent' metals, silicic acid, aluminates or other. salts capable ofswelling with water or of forming liquid crystals. Amongv organichydrophile colloids that may be used are polysaccharides, such ascellulose or starch, gum .arabic, agar-agar, lipoides, proteins, such ascasein or albumen, organic dyestuffs and the like. The substancesrepelling the solvating agent, such as .vater, which are to be used incombination with hydrophile colloids, are particularly oils,

such'as mineral oils, oil fractions and residues,

tar oils .and the like. Such repellent substances are indicatedhereinafter as hydrophobic."

Where, however, the solvating agent consists of organic liquids, such asoils, hydrocarbons,

chlorinated hydrocarbons, alcohols, carbon di'- sulphide and the like,then the swellable substance may' comprise, for instance, rubber,balata, shellac, drying oil polymerisation products, factis,nitrocellulose, acetyl cellulose, soaps and the like which are termedhereinafter in this connection as oleophile colloids. In the case ofsolvating agents consisting of organic liquids such as oils, which areused in conjunction with oleophile colloids as above explained, thesubstance repelling the solvating agent will be. an oleophobic substancein most instances water or an aqueous liquid.

The process according to the invention can be carried out in differentways and with the use of various substances, according to the prevailingconditions and the effect to be obtained. Some embodiments of theinvention are described hereinafter more in detail.

The swellable substance, forinstance, a hydrophile colloid, may besuspended in a hydrophobic substance and th said suspension is caused topenetrate, either together with or without the solvating agent, into theobject or mass to be treated; similarly use can be made of an oleophilecolloid suspended in an oleophobic substance and applied either togetherwith or without the solvating agent.

The particles of the hydrophile or-oleophile colloid may also be coatedonly with a thin film, such as an adsorption film of a hydrophobic oroleophobic substance, in which case a carrier or suspending agent isrequired, which at the same time may act as the solvating agent.

Further, the above embodiments may be combined, when, for instance, thehydrophobic substance going with the hydrophile colloid is the solvatingagent for the oleophile colloid, and/or the oleophobic substance goingwith the oleophile colloid is the solvating agent for the hydrophilecolloid.

The properties of the hydrophobic substance,

when using a hydrophile colloid, or the properties of the oleophobicsubstance, when using an oleophile colloid, render it possible tocontrol the rate of salvation. This control may be eilected, for.

substance,in connection with the nature and quantity of the respectivehydrophile or oleo-' phile colloid, and moreover the rate and degree oi.swelling can be varied by a suitable control of the acidity and thepolarity of the substances used, which properties may be altered, ifdesired, by added substances.

In a special embodiment the hydrophile or oleophile colloid may beformed during the penetration of the treating agents into the mass undertreatment, in which case the rate of formation of the colloid may alsoserve as a controllable factor in the working of the process.

The treating agents according to the invention may be applied accordingto the processes generally used for introducing the known impregnatingagents into earthy or stony masses. As a rule the treating agent oragents may be caused to penetrate into the mass to be treated by meansof pipes, so that a proper impregnation is effected at the requiredplace, whereby the desired impermeabilisation or consolidation isproduced.

The treating agents may be injected or pumped in under normal orincreased pressure, the pressure applied being, it desired, so high asto produce a widening of the voids with a view to ensuring a moreeificient penetration of the liquids. The mass to be treated may also besubjected, either beforehand or simultaneously, to a separate treatmentfor altering its structure or the chemical constitution of the materialto be im-- pregnated, for example by injecting suitable liquids orgases, or by washing out some soil components or removing them inanother manner.

The process according to the invention may,

if desired, be combined with other known consolidating andimpermeabilising processes, such as the application of bitumendispersions, cement or clay suspensions, or chemicals whichby mutualreaction form voluminous precipitates. More particularly, thepracticability of said known processes may be improved by combining themwith the present process. For instance, in carrying out the so-calledsilicatisation process, according to which consolidation andimpermeabilisation is produced by the separate injection of solutions ofaluminium sulphate or calcium chloride, and waterglass, as a ruleclogging up immediately occurs at the place of introduction, owing torapid precipitation.

V The process according to the invention may also be carried out bysuccessively injecting mixtures showing diiferent rates of salvation;this may be advantageous, for instance, in those cases where flushingaway 01- the injected liquids by running water, such as by the groundwater, is to be feared.

In some cases only a temporary tightening or consolidation may be aimedat. which according to the invention may be achieved, for instance,

by using indefinitely swellable substances, such as gums or proteins,which aiter some time are washed out again by water, or organicswellable A water-bearing gravel layer is treated by simultaneously butseparately injecting through pipes in the proportion 1:1 on the one handa 10% colophony solution in a gasoline rich in arcmatics, and on theother hand a 5% aqueous aluminium chloride solution. The acids containedin the colophony are converted into aluminium salts, which swell byabsorbing gasoline.

Example 2 In order to consolidate the base of a dune, pipes are drilledinto the sand at a shallow depth, and

a mixture of one part of finely powdered aluminium sulphate, suspendedin two parts of spindle oil, and flve parts of a 20% water-glasssolution is injected through these pipes. Owing to the coating of thealuminium sulphate with spindle oil, the precipitation oi aluminiumsilicate proceeds so slowly that a uniform tightening and sonsolidationof the sand can be obtained over a considerable depth and width ofinjection.

1. A process for improving the cohesion 01 and for impermeabllizing andconsolidating, grounds and other earthy and stony masses and structures,which comprises simultaneously but separately injecting into the massesa solution of colophony in solvent and an aqueous solution of analuminum compound adapted to convert the acids contained in thecolophony into aluminum salts which swell by absorbing the solvent inwhich the colophony is introduced.

2. A process for improving the cohesion and for imperme'abilizing andconsolidating, grounds and other earthy and stony masses and structures,comprising injecting into said masses two substances which reactchemically wlth each other to form a precipitate, one of said substancesbeing coated with a film of a third substance which retards theprecipitate-forming reaction.

3. A process according to claim 2, wherein the materials are injected inthe form. of a mixture oi! one of the reacting substances suspended insaid precipitate-retarding agent, and an aqueous solution of the'otherof said reacting substances.

ammrr HENDRIX w: LEEUWEN.

